A battery module that is used as a power source of an electric vehicle or a hybrid vehicle is disclosed in Patent Document 1. Such a battery module includes a plurality of batteries each having electrode terminals and adjacent electrode terminals are connected by a battery connecting assembly such that the batteries are connected in series or in parallel. The battery connecting assembly is configured with a plurality of connection units that are connected to each other. Each connection unit has a connection member that connects the adjacent electrode terminals.    [Patent Document 1] Japanese Unexamined Patent Publication No. 2011-8957